Use of @ in sql statements or in declaring variables?

Is there anyone who told me what is开发者_运维知识库 the use of @ in sql statements specially while declaring variables in sql query......thnx for any response.

It's kind of hard to Google for an @ sign isn't it?

Here's a link to SQL Server help on this, where it says:

Variable names must begin with an at (@) sign.

And here's a link about declaring variables in PL-SQL, where they are not preceded by the @ sign.

So, it depends on which particular database you're using.

It is used to declare variables. For example:

Declare @SubID varchar(20)

Declare @MyTable Table 
(
   Column1 int
)